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Wed, 2 Sep 2026 23:00:45 +0000 (UTC) Received: from dovecot-director2.suse.de ([2a07:de40:b281:106:10:150:64:167]) by imap1.dmz-prg2.suse.org with ESMTPSA id LpHeMZ2qmGqZCgAAD6G6ig (envelope-from ); Wed, 02 Sep 2026 23:00:45 +0000 From: Gabriel Krisman Bertazi To: axboe@kernel.dk Cc: io-uring@vger.kernel.org, Gabriel Krisman Bertazi Subject: [PATCH 0/2] Fix return with MSG_TUNC overtruncating buffers Date: Wed, 2 Sep 2026 20:00:39 -0300 Message-ID: <20260902230041.1320658-1-krisman@suse.de> X-Mailer: git-send-email 2.55.0 Precedence: bulk X-Mailing-List: io-uring@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Spam-Score: -2.80 X-Spam-Level: X-Spamd-Result: default: False [-2.80 / 50.00]; BAYES_HAM(-3.00)[99.99%]; MID_CONTAINS_FROM(1.00)[]; NEURAL_HAM_LONG(-1.00)[-1.000]; R_MISSING_CHARSET(0.50)[]; NEURAL_HAM_SHORT(-0.20)[-0.993]; MIME_GOOD(-0.10)[text/plain]; MIME_TRACE(0.00)[0:+]; TO_DN_SOME(0.00)[]; RCVD_VIA_SMTP_AUTH(0.00)[]; ARC_NA(0.00)[]; DKIM_SIGNED(0.00)[suse.de:s=susede2_rsa,suse.de:s=susede2_ed25519]; TO_MATCH_ENVRCPT_ALL(0.00)[]; FROM_HAS_DN(0.00)[]; RCPT_COUNT_THREE(0.00)[3]; FROM_EQ_ENVFROM(0.00)[]; DBL_BLOCKED_OPENRESOLVER(0.00)[suse.de:mid,imap1.dmz-prg2.suse.org:helo]; RCVD_COUNT_TWO(0.00)[2]; RCVD_TLS_ALL(0.00)[] X-Spam-Flag: NO Jens, This is an attempt to fix the issue reported at [1]. It works by splitting the return size (which can be the full size of the packet) from the value actually commited in the buffer. Please, let me know your thoughts. Patch 1 is a small preparation and patch 2 has the fix. This was tested for regressions against liburing as well as using the reproducer from the bug, which I can turn into a proper test case against liburing. I sent this before but the submission was botched. Please take this version in consideration. Thanks, [1] https://github.com/axboe/liburing/issues/1619 Gabriel Krisman Bertazi (2): io_uring/net: let io_recv_buf_select return the length of the buffer region io_uring/net: don't overconsume buffers when using MSG_TRUNC io_uring/net.c | 48 +++++++++++++++++++++++++++++++++++++----------- 1 file changed, 37 insertions(+), 11 deletions(-) -- 2.55.0